Module Lowest common ancestor (LCA)

Lowest common ancestor (LCA)

**Frequency: 8/10** In many cases where a problem involves querying a path on a tree, there is a high likelihood that the Lowest Common Ancestor (LCA) will be a crucial element in the solution. There are also a lot of problems involving LCA in the next module, Euler tour.

Resources

- [CP Algorithms: Lowest Common Ancestor - Binary Lifting](https://cp-algorithms.com/graph/lca_binary_lifting.html)

Problems

LCA 433 / 439 1300
Distance query 391 / 401 1400
Robot on tree 321 / 345 1400
Heaviest edge 304 / 310 1500
Equal path 239 / 251 1500
Triplet 203 / 206 1500
Path update 227 / 233 1600
Second best minimum spanning tree 109 / 185 1700
Oggy and the cockroaches 34 / 53 1800